For the increasingly aging population, the quest to look younger has become more important than ever. The anti-aging market is booming and represents the “key growth engine” for the entire skin care industry. Consumers have high expectations for the efficacy of skin care and want to see visible results. Formulating effective anti-aging products requires a thorough understanding of consumers’ cognitive and emotional needs, formulation chemistry, and most of all, the biology of skin aging.1

Perceived age is the marker for facial aging.2 Aging affects the texture and color of skin as well as the shape of the face. Facial skin movement is controlled by complex muscular networks that allow for functions such as eating, breathing, vision or speech in addition to social behaviors that communicate emotions such as facial expressions. These movements are also partially responsible for facial aging.

The Biology of Skin Aging

The process of skin aging is complex and multifactorial, as structural, functional and aesthetic changes happen at a variable rate. It is misleading to consider skin aging as a uniform biological event; several distinct biological processes may occur concurrently.3 There are five types of skin aging, including: intrinsic, extrinsic, lifestyle, hormonal or catabolic.

Intrinsic, chronological aging reflects the passage of time from gravity and genetics. Extrinsic aging is usually attributed to photoaging and smoking. Lifestyle or behavioral aging includes diet, alcohol and drugs. Hormonal aging involves dysfunction or aging of hormonal systems. Finally, catabolic aging is related to chronic diseases. These types will be explained here.

Intrinsic aging: Intrinsic skin aging is a slow process with clinical features such as smooth, pale, dry and less elastic skin having fine wrinkles that are not apparent until old age. Intrinsically aged skin shows epidermal and dermal atrophy, a reduced number of fibroblasts, less collagen and more matrix metalloproteinases (MMPs). Its structurally altered dermal-epidermal junction (DEJ) may contribute to increased skin fragility and reduced nutrient transfer between the dermal and epidermal layers.4

Smoking also accelerates aging, causing the degradation of elastic fibers and a significant increase in facial wrinkles. The wrinkles of smokers are deep and narrow, compared to nonsmokers. This pattern of wrinkling is referred to as “smoker’s face” and often is accompanied by gaunt features and atrophic, gray, uneven skin color.5 Further, pursing the lips and squinting while inhaling smoke may lead to the formation of sharply contoured crow’s-feet and prominent peri-oral lines.

Hormonal and catabolic aging: The skin is a hormone-dependent organ, and the decline of hormonal secretions during menopause accelerates skin aging. Menopause appears as a turning point in life, with a decline in skin qualities.6 Estrogen in particular has a profound effect on skin, encouraging extracellular matrix production and preventing decreases in collagen, skin thickness, skin hydration and epidermal barrier function.7 Increased sagging, as opposed to coarse wrinkles, is the main symptom of postmenopausal aging.8 Catabolic aging compromises older skin further through the impact of a specific chronic disease, such as diabetes, hypothyroidism, cancer or infection.

Holistic Approach

Anti-aging skin care technologies have become increasingly high-tech, targeting specific cellular phenomena. However, as illustrated above, skin aging is the sum of several concurrent aging processes, which differ in aging contribution among individuals. Photoaging has received more attention in research and the media but is only one aspect of the aging process. Although the rationale for sun protection is widely advocated, people still associate it with occasional holiday exposure.9

Photoaging affects people of the same age and photo-type differently,10 and might not become apparent for decades after the initial damage. To ensure good environmental protection, daily skin care products containing a combination of SPF 20+ and a spectrum of antioxidants should be used.

Postmenopausal skin aging is often neglected in the “classical” aging concept, as its impact is difficult to estimate. In women, intrinsic and postmenopausal aging are linked. There is an array of technologies designed to aid skin changes from intrinsic aging or menopause, e.g., keratinocyte and fibroblast proliferation and repair of the DEJ. Examples of actives clinically tested, although on forearms and not facial skin, include c-xyloside, which was shown to repair the DEJ,11 and bifidobacterium-fermented soy milk extract, which improved skin elasticity.12 In the absence of advanced diagnostics, preventive measures should target each of these processes.

Skin aging is an interplay of the different types of aging that differs between individuals; the best approach entails the use of multifunctional active ingredients that address more than one type. Also, shifting consumer attitudes toward a more holistic approach to skin health represents the next educational challenge for the skin care industry.